Best way to add custom / magic / flutter fields into RSS feed

Using WordPress 3, creating write panels with Magic Fields, how do I add custom fields to my RSS feed?

For example, I have an ‘image of the day’ write panel, with a custom field for the photo credit. How can I include all that as part of my feed?

Thanks.

you can use something like this

function feed_magic_fields( $content ) {
  global $post, $id;

  if ( !is_feed() )
    return $content;

  // is feed
  $date = get('date_event');
  if( $date)
    $content .= $date

  return $content; 
}

add_filter( 'the_content', 'feed_magic_fields' );